docs: def update_instance(self, uid, body):
          """
          Update an Model via a PUT request
  
          :param str  uid:  String identifier for the list resource
          :param dict body: Dictionary of items to PUT
          """
          uri = "%s/%s" % (self.uri, uid)
          response, instance = self.request("PUT", uri, data=body)
          return self.load_instance(instance)